Open AccessStarspot distributions on XY UMa during 1997–2000 from eclipse mapping
Author(s) -
Lister T.A.,
Collier Cameron A.,
Hilditch R.W.
Publication year - 2001
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2001.04712.x
Subject(s) - starspot , physics , ephemeris , eclipse , light curve , astrophysics , binary star , astronomy , stars , satellite
We present narrow‐band red light curves and surface maps of the short‐period RS CVn binary system XY UMa, obtained between 1997 January and 2000 March. The light‐curve morphology of this system is known to vary on time‐scales of a few days. We have used eclipse‐mapping techniques to map the distribution of cool starspots on the surface of the primary star. The resulting maps show the continued evolution of spot features on time‐scales of a few days to a week. By comparison with the images of Collier Cameron & Hilditch, we also find evidence for longer term trends, including a decline to an activity minimum during 1997 and a rise in activity during 1998–2000. We also find marginal evidence from the O–C ephemeris curves for a periodicity and a peak corresponding to the time of activity minimum.